Circuit breaker



S. S. GREEN CIRCUIT BREAKER Feb. 28, 1933.

Filed Nov. 5, 1928 @15430: new

Patented Feb. 28, 1933 UNITED STATES' PATENT oFFIcE STANLEY S. GREEN, OFINDIANAPOLIS, INDIANA, ASSIGNOR TO DUNCAN ELECTRIC MANUFACTURINGCOMPANY, OF LA .'EAYETTE, INDIANA, Av CORPORATION 0F ILLINOIS CIRCUITBREAKER .Application led November It is the general object of my presentinvention to produce a dependable liquid-conductor reclosable cut-out orcircuit controller co-pending application Serial No.A 285,114,

' ductor a supplementa tiled J une 13, 19,28.

The structure of this present application, however, while dominated bysaid co-pending application, relates to certain additional features notdisclosed in said co-pending and generic application.

The main distinguishing objects of the'invention of this presentapplication are:

1. To provide a supplemental excess-current circuit-breaking device,desirably in the form of va fuse located within the circuit controller,which will serve to break the'circuit inthe case of some unusualemergency, as upon enlargement ofthe restricted portion if said passage.

, 2. To provide separate from the electrodes and the co-operating art ofthe liqiliid consafety-switc .action by which an'additional'breaking ofthe current occurs in. manual operation, and which serves -as asupplemental break in the circuit during the action'ot` re-establishingthe connection through the liquid conductor between electrodes.

3:"10 provide a filling and venting arrangement by which the liquidconductor is fed into the current-limiting passage from the same end atwhich it is in the main discharged upon excessive current, and from theend which is normally uppermost of said passage; and by which theventing is-qbtained from the opposite end of` said passage.

The accompanying drawing illustrates my invention in certain preferredforms, inde pendently of any mounting and of any definitecurrent-supplying means, as they may take many forms. In such drawing,Fig. 1 is a longitudinal section of a cut-out or circuit' controllerembodying my invention,

5, 1928. Serial No. 317,221.'

with the device in the off position; Fig..

tion -of the device shown in Figs. 1 and 2,`

and is viewed with the device in an intermediate position between offand normal on positions; Fig. 4 is a view generally similar to Fig. 1,with the device in off position, but. showing a modiiication in whichthe supplemental switching mechanism is external instead of internal;and Fig. 5 is an elevation of the modification shown in Fig. 4, on asmaller scale, and with the device in fnormal on7 position.

[I will first describe my invention in connection with the structureshown in Figs. 1, 2, and 3.

Inthis form, there is a main cup-shaped insulating. shell 10, which asshown is pivotally mounted on transverse pivot pins 11 whereby thedevice may be swung between the positions shown-in Figs. 1 and 2. Theopen end of this shell is closed by a plug 12, also desirably ofinsulating material, which is held in place in any suitable manner, asby cement and a tight fit. On its lower side, the cup-shaped shell 10 isprovided with an opening 13, which receives the upper end of a secondinsulating plug 14; which may also be held in place in anysuitablemanner, as by cement and a tight tit. v

On the lower end of the plug 14 is mounted a metal cap 15, which is atonce one of the terminals ,of the device and one of the electrodes. Ashere shown, the cap 15 has a threaded stud lextending outwardtherefrom,to which one of the lead-in wires 17 may be attached as to abinding post, such wire here being s'utliciently flexible to permitthe.v

each other at the lower end of the plug 14, as by a depression 23 formedin the inner face of the cap 15. The hole 20 is provided,

, sectional area when that portion 24 is filled with the liquidconductor 25; which is most conveniently mercury. The sie of thisrestricted portion 24 may vary with the value of the maximum current atwhich it is intended that the device shall operate to break the circuit.

The second electrode of the device is in the form of a metal rod 30,which projects from a suitable metal plug 31 into the upper end of thehole 20. The plug 31 is suitably mounted Vin the upper side of the innerwall of the shell 10, desirably substantially oppositethe hole 20; andmay be held in place by the molding of the insulating material aroundit. The plug 31 is connected by a wire 32 to a similar plug 33 similarlymounted in the inner side wall of the shell 10 near its closed end. Theplug 33 is on the lower .side of the shell 10, so that the mercury maylie upon or against it by gravity when the device is in the positionshown in Fig. 2, whereas that cannot happen with the plug 31 in eitherposition illustrated or in any intermediate position as the device ismoved clockwise from the position shown in Fig. l to the position shownin Fig. 2. The wire 32 is desirably a supplemental protective device, bybeing of such material and cross-section that it serves as a fuse tobreak the circuit upon a predetermined excess of current over the normalmaximum which the mercury in the restricted passage 24 is designed topermit. 1

1n the closed end of the shell 10 is mounted a plug 35, which has a headexposed Within the shell and an external threaded shank 36 to which thesecond lead-in wire 37 may be attached as to "a binding post. Thelead-in wire 37, like the lead-in wire 17, is here sumciently flexibleto permit the desired movements of the device.

When the device is in the position shown in Fig. l, or off position, themercury 25 flows as necessary into the hole 20, to till such hole and toiow from the bottom thereof into the lower end of the tube 22 and upsuch tube until the mercury in the tube reaches substantially the samelevel as that in the shell 10. This is the position of the device inwhich the restricted passage 24 is filled with mercury; and the illingis from the top, and the venting which permits such filling is from thisbottom of the hole 20. With the device inffthis position shown in` Fig.1, the circuit isbroken between the plugs 33 and 35, as those plugs arespaced apart, and in this position' of the device there is yno mercurybetween them to interconnect. them. Thus the plugs 33 and 35, inconjunction with the mercury, serve asthe switching device.

When the device is tilted from the position shown in Fig. 1 in aclockwise direction to the position shown in Fig-2, the mercury in thehole 20 and tube 22 remains there; but the excess mercury which was atthe left end of the shell 10 when the device is in the position shown inFig. 1 ows to the right along such shell upon such tilting, and lillsthe corner between the plugs 33 and 35; thus connecting those plugs andclosing the circuit. Thus the circuit closing occurs at a point remotefrom the electrodes 15 and 30,` andyby mercury which is not in contactwith those electrodes.

Tf now it is desired to break the circuit manually, the device may betilted counterclockwise from the position shown in Fig. 2 to theposition shown inFig. 1. YThis causes the mercury which was in the rightend of the shell 10, and which there connected the plugs 33 and 35together, to flow from that end of the shell to the left end of theshell, and out of contact with those plugs; thus breaking the circuit atsuch plugs and so at a point remote Jfrom the electrodes 15 and 30.

1f with the device in the position shown in Fig. 2, the value of thecurrent exceeds the normal maximum, the mercury in the restrictedportion 24 of the hole 20 is vapor- -mercury out of Contact with theelectrodes 15 and 30; and is the normal automatic circuitbreaking actionupon normal overloads.

When this automatic breaking of the cir'- cuit occurs, it is necessaryin order to re-close the circuit to tilt the device from the positionshown in Fig. 2 to the position shown in Fig. 1, and then to return itto the position shown in Fig. 2. The tilting from the position shown inFig. 2 to the position shown in Fig. 1 first produces an additionalbreak in the circuit betweenthe plugs`33 and 35 by reason of the flow ofthe mercury from the right end to the left end of the shell 10. Suchmercury iows fromthe left end of the shell 10 into the tube 20, and thusagainrefills such tube from the top, with a venting from the bottom ofthe hole 10 through the tube 22. When the hole 2O has thus heenreilled,to produce a connection between the electrodes 15 and 30, the'subsequent tilting of the device from thc position shown in Fig. l totheposition shown in Fig. 2 causes the excess mercury beyond thatrequired to fill the holes 2O and 21 to ow to the right to connect againthe plugs 33 and 35, and thus re-establish the circuit.

'. The tube 22 projects upward beyond the upper end of the plug 14, asbefore explained so that there will be no possibility veither ofre-filling the hole by way of the hole 21, or of providing-acurrent-path through the tu'be 22 in shunt tothe current-restrictingportion of the liquid conductorin the restricted portion 24 of the holeV20. That is, this projection' of the tube 22 prevents the unintendedenlargement of the current-capacity of the device by any such shuntpath. as well as ensuring filling of the hole 20 from its top.

In case the restricted portion 24 of the hole 20 becomes enlarged forany reason, or any other connection is made between the electrodes 15and 30 as by a cracking of the plug 14, so that there results aconnection between the two electrodes having a current- Icarryingcapacity in excess of the normal maximum, the fuse 32'comes into play tobreak the circuit when and if the current eX- ceeds such excess capacityabove the normal maximum. That is, in case the connection between theelectrodes 15 and 30 is for any reason enlarged in current-carryingcapacity beyond the current-carrying capacity of the fuse 32, and thecurrent rises to a value in excess of that capacity, that fuse fuses tobreak the circuit; even though the mercury or anything else stillinterconnects the electrodes 15 and 30.

In the modification shown ,in Figs. 4 and 5, the parte 1o, 11, 12, 1a,14, 15, 2o, 21, 22, 23, 24, 25, and 30 are substantially the same as inthe arrangement shown in Figs. 1, 2, and 3; save that the electro-de30', or desirably a portion 30 thereof, may be slightly smaller incross-section, so that it itself serves as an emergency fuse in caseanything happens to prevent the vaporization of the mercury in therestricted portion 24 of the hole 20. That is, the portion 30 of theelectrode 30 in the arrangement shown in Fig. 4 takes the place of thefuse 32 of the arrangement shown in-Figs. 1, 2, and 3, in providinganemer-- gency fuse.

In the arrangement shown in Figs. 4 and 5, moreover, the-internal-switching action obtained between the mercury and the plugs 33and 35 of the arrangement shown in Figs. 1, 2, and 3 is removed from theinterior of the device to the exterior thereof. To this'end, instead ofhaving a stud 16, the electrode 15 is provided with a switch blade 40,which co-operates with spring fingers 41; and the Vvplug 31 is projectedthrough the shell 10 to the exteriorv thereof, and is there providedwith a switch blade 42 which co-operates with spring fingers 43.

Fig. 5 shows the device in normal on position, corresponding to theposition of Fig. 2. The normal :automatic circuit-breaking shown; whichbreaks the circuit by separatby vaporization of the mercury is the sameas in the arrangement shown in Figs. 1 and 2; and it is necessary tomove the device of Fig. 5 counter-clockwise to the position shown inFig. 4 to re-fill the hole 20 and tube 22, and then to return it to theposition shown in Fig. 5 in order to re-establish the circuit.

However, upon such movement of the device in counter-clockwise directionfrom the position shown in Fig. 5, the switch blades 40 and 42 aredisengaged from the spring fingers 41 and 43, to provide supplementalbreaks in the circuit; so that the circuit is not closed when the hole20 and tube 22 'are 80 filled with mercury while the device is in theposition shown in Fig. 4, and is not closed'until the device is returnedto the position shown in Fig. 5 and the switch blades 40 and 42 arere-engaged with the spring fingers 41 and 43.

In the same way, to break the circuit manually with the device shown inthe position of Fig. 5, such device is turned in a counterclockwisedirection from the position there ing the switch blades 4() and 42 fromthe spring fingers 41 and 43.

I claim as my invention: 1. An' electric circuit controller, comprisinga. container movable to different controlling positions, a conduithaving its passage communicating with saidcontainer at two separateplaces, a quantity of liquid conductor located within the space formedby said container and passage buttoo small to fill it, one of saidcommunicating places between the conduit and the container being at alltimes above the level of any liquid conductor in the container and theother being above such level when the container is in one position 'butbelow such level when the container is in 4duit to break the connectionprovided through the conduit between the two electrodes, the parts beingso arranged that such blowing out is vmainly at th at Acommunicatingplace which is capable of being submerged.

2. An electric circuit controller, compris` ing a container movable tooff and normal on positions, a conduit having its passage communicatingwith ysaid container at two separate places, a quantity of liquidconductor located within the space formed by said container and passagebut too small to fill it, one of said communicating places between theconduit and the container being at all times above the level of anyliquid conductor in the container and thel other being above such levelwhen the container is in normal on position but below suchilevel when`provided by said conduit, said conduit beingarranged so that ,uponexcess current there occurs a vaporization of liquid conductor withinthe conduit that blows liquid condu-ctor out of the conduit to break theconnection provided through the conduit between the ,two electrodes,said electrodes being so arranged with respect to the conduit Ithat theblowing out ,of the liquid conductor is mainly at the communicatingplace which can be submerged below the level of the liquid conductor bya movement of the container to the olf position.

8. An electric circuit controller, comprising a container movable to 0Hand normal on positions, a conduit having the two ends of its passageseparately communicating with .said container, liquid conductori locatedwithin the space formed by said container and passage, and twoelectrodes which may be connected together by liquid conductor in saidconduit when-said container is in normal on7 position; saidparts beingso arranged that upon excessive current there occurs vaporizationofliquid conductor in said passage and resultant blowing out of liquidconductor mainly from one end of said passage to break theleireuit,that, end of the conduit being above the level of any liquid conductorin the container save when the container is moved to off position andthen being below such level, and the -opposite end of the conduit.beinghigher than the first end thereof when the container is in oftposition. 4

4. An electric circuit controller, comprising a container movable to 0Rand normal on positions, a conduithaving the two ends of its passageseparately communicating with said container', liquid conductor locatedwithin' the space formedby said container and passage, and twoelectrodes which may be connected together by liquid conductor in saidconduit when said container is in normal on position; said parts beingso arranged that upon excessive current there occurs Vaporization ofliquid conductor in said passage and resultant blowing out of liquidconductor mainly from one end' of said passage to break the circuit,both ends of the conduit being above tlielevel of any liquid conductorin the container when the container is in normal on position, and oneend of the conduit being above such level for both positions of thecontainer, said latter end being the opposite end of the conduitfrom'that at which the aforesaid blowing out of the liquid conductormainly occurs.

5. An electric circuit controller, comprising a container movable to oliand normal on positions, liquid conductor within said container, aconduit having a passage communicating at both ends with said containerand including a smaller current-limiting portion which has itsendsnormally at diierent heights and at which vaporization of liquidconductor occurs upon excessive current to blow liquid conductor out ofsaid passage to break the circuit, said passage being arranged to bere-filled from the end thereof which leads to that end of -saidcurrent-limiting portion which is uppermost when the circuit is closedand upon such re-lilling to be vented from the .end which leads to thatend of said current-limiting portion which is lowermost when the circuitis closed.

6. An electric circuit controller, comprising a movable container,liquid conductor contained therein, a conduit having its passagecommunicating with said container at two separate places, two electrodeswhich may be connected together by liquid conductor in said passage,said passage having a portion of such size that upon excess current-Howthere occurs therein vaporization of liquid conductor to blow liquidconductor out of said passage to break such circuit between suchelectrodes, said parts being so arranged that the container mustbe-tilted to another position from that at which such blowing outoccurred in order to re-lill said passage to re-connect said electrodes,and switching mechanism separate from but in series with said electrodesfor closing the circuit when the container is in the position where suchblowing out may occur and for opening the circuit when the container isin said passage-filling position.

l. An electric circuit controller, comprising a movable container,liquid conductor contained therein, a conduit having its passageAcommunicating with said container at two separate places, two electrodeswhich may be connected together by liquid conductor in said passage,said passage having a portion of such size that upon excess current-flowthere occurs therein vaporization of liquid conductor to blow liquidconductor out of said passage to break such circuit between suchelectrodes, said parts being so arranged that the container mustbe-tilted to another position from that at Iwhich such blowing outoccurred in order to re-illsaid passage to reconnect said electrodes`and switching mechanism separate from but in series with said electrodesfor closing the circuit when the container is in the position where suchblowing out may occur and for opening the ci'rcuit when the ycontaineris in said passage,- filling position, said switching mechanism and saidcontainer being operable in 'coniinon.

8. An electric circuit controller, comprisby liquid conductor insaidpassage, said' electrodes which may be connected together passage havinga portion of`such size that upon excess current-flow there occurs'therein vaporization of liquid conductor to blow li Y uid conductor outof said passage to brea such circuit between such electrodes, saidkparts being so arranged that ,the container must be tilted to anotherposition from that 10 at which such blowing out occurred in order tore-fill said passage t0 re-connect said electrodes, and switchingmechanism separate from but in series with. said electrodes Vforvclosing the circuit when the container is in the position where suchblowing out may occur and for opening the circuit when the container isin said passage-filling position, said switching mechanism being locatedwithin said container and including two members which are connectible bysaid liquid conductor separate from but in series with said electrodes.

9. An electric circuit controller, comprising a movable container, aconduit having its passage communicating with said container, liquidconductor located within the space formed by said container -andpassage, two electrodes which may be connected together by liquidconductor in said passage, said passage having a portion of such sizethat upon excessive current there occurs therein vaporization of liquidconductor to blow liquid conductor out of the tpassage and thus breakthe circuit between the electrodes; and an emergency fuse device havinga greater currentcarrying capacity than the normal currenty carryingcapacity of the liquid conductorbetween said electrodes, so that in casethecurrent-carrying capacity between the electrodes is increased in anymanner said supplemental fuse comes into play to break the circuit vwhena definite higher excess-current value is reached than the normalexcessive-current value to which the device is responsive.

, -.10. Anelectric circuit controller, comprising a movable container, aconduit having its passage communicating with said container,

vliquid conductor located l,within the space formed by said containerand passage, two electrodes which. may be'connected together. by liquidconductor in said passage, said passage having a portion of such sizethat upon excessive current there occurs therein vaporization of liquidconductor to blow liquid conductor out of the passage. and thus breakthe circuit between the electrodes; and an emergency fuse device havinga greater current-carrying capacity than the normal current-carryingcapacity of the liquid conductor between said electrodes, so that incase the current-carrylng capacity between the v electrodes is increasedin any manner'said supplemental fuse comes intoplay to break the circuitwhen a definite higher excess-current value is reached than the normalexcessive-current value to which the device is responsive said emergencyfuse device being located within said container but separate from theelectrodes.

11. An electric circuit controller, compris.- ing a movable container, aconduit having its passage communicating with said container, liquidconductor located, within the space formed by said container andpassage, two electrodes which may be connected together by liquidconductor in said passage, said passage having a portion of such sizethat upon excessive current there occurs therein vaporization of liquidconductor to blow liquid conductor out of the passage and thus break thecircuit between the electrodes; and an emergency fuse device having agreater current-carrying capacity than the normal current-carryingcapacity of the liquid conductor between said electrodes, so that incase the current-carrying capacity between the electrodes is increasedin any manner said supplemental fuse comes into play to break thecircuit when a definite higher excesscurrent value is reached than thenormal excessive-current value to which the device-is responsive, saidemergency fuse device being located within said container.

l2. An electric circuit controller, comprising a movable containerhaving a plurality of controlling positions including a normalcircuit-closing position, a quantity of liquid conductor within thecontainer, a tube of heat-resisting insulation having one end com- Imunicating with the container, a conduit which interconnects the otherend of said tube with the container, two electrodes connectible togetherby liquid conductor when it is in and extends along a substantialportion of the length of said tube, and connecting means co-operatingwith the electrodes and through which the electrodes may be connected ina circuit, said container, conduit, and tube having a shape and relationwhich constrain passage of the liquid conductor by gravity from thecontainer. through the tube and into the conduit upon a predeterminedmovement of the container away from said normal circuit-closingposition.

' 13. An electric circuit controller, comprisprevent its returnthereinto while the container is in normal circuit-closing position.y

14. An electric circuit controller, comprising a movable containerhaving a plurality of controllingpositions including a normalcircuit-closing position, a quantity of liquidfeonductor within thecontainer, a tube of heat-v resisting insulation having one endcommunii. lcating vwith the container, a conduit which interconnects theother 'end of said tube with the container, two electrodes connectibletogether by liquid conductor when it is in and ,extends along aIsubstantial portion of the length of said tube', connecting meansco-operating with .the electrodes and through which the electrodes maybe connected lin a f circuit, and an emergency Jfuse-element supportedby the container and in series with the electrodes, said fuse elementhaving `a current-carrying capacity in predetermined eX- cess of thenormal current-carryingv capacity of the liquid conductorinterconnecting the electrodes.

15. An electric circuit controller as set forth in claim 12, with theaddition of an emergency fuse element supported by the container and inseries with the electrodes, said 'fuse element having a current-carryingcapacity in predetermined excess of the normal current-carrying capacityof the liquid conductor interconnecting the electrodes.

16. An electric circuit controller, comprising a movable containerhaving a plurality of controlling positions including a normalcircuit-closing position, a quantity of liquid conductor within thecontainer, a. tube of heat-resisting insulation having its passagecommunicating with the container, two electrodes arranged for connectionto a circu t and connectible together by liquid conduct rr when it is inand extends along a substanti l portion of the length of said tube, andan emergency fuse element supported by the container and in series withthe electrodes, said fuse element having a current-carrying capacity inpredetermined excess of the normal current-carrying capacity of theliquid conductorinterconnecting the electrodes.

17.@An electric circuit controller as set forth in claim 16, with theaddition that said 'container and tube have a shape and relation whichupon the expulsion ot liquid conductor -from the tube prevent its returnthereinto while the container is in normal circuit-closing position.

aseaeee the space providedby said container and conduit, and twoelectrodes associated with said conduit to be interconnectible by saidliquid conductor extending through said currentlimiting conduit-portionto provide a current path lengthwise thereof; said circuit controllerbeing provided with means for feeding said liquid conductor at will intothe aforesaid passage-portion at the higher end thereof. l

19. An electric circuit controller having a movable member, andcomprising a container, a' tubular conduit opening at both ends into acommon space in said container, said con-V duit having a passage-portionwhich is highei` at one end than at the other when the circuit throughthe circuit controller is.

closed and which includes a current-limiting vportion of predetermineddimensions, liquid conductor within the space provided by `saidcontainer and conduit, and two electrodes associated with said conduitto be interconnectible by said liquid conductor extending through saidcurrent-limiting conduit-portion to provide a current path lengthwisethereof; the aforesaid passage-portion being associated with saidmovable member to have said liquid conductor fed into it at the higher.end thereof by movement of said movableV member, and under suiiicienthead to overcome any surface tension tending to prevent such'feeding. v

20. An electric circuit controller having a movable member movable to 0Hand normal on positions, and comprising a container, a tubular conduitopening at both ends within said container, said conduit having acurrent-limiting portion which is of predetermined dimensions and ishigher at one end than at the other when said movable memben is innormal on7 position, liquid conductor within said container and conduit,and two electrodes associated with said conduit to be interconnected bysaid liquid conductor eX- tending through said current-limitingconduit-portion but otherwise insulated from each other; saidcurrent-limiting conduitportion being associated with saidmovable memberto have liquid conductor fed to it at its higher end by movement of themovable member.

21. An electric circuit controller comprising a container, liquidconductor in the container, a current-limiting insulating tube havingits two ends separately communicating with the container atsubstantially diierent levels, two electrodes interconnectible by liquidconductor along a current path extending lengthwise through said tube,said container and tube being provided with means to .feed liquidconductor from the container the container, two electrodesinterconnectible by liquid conductor along a current path extendinglengthwise through said tube, said container and tube being providedwith In witness whereof, I have hereunto set my hand at Indianapolis,Indiana, this 2d day of November, A. D. one thousand nine hundred andtwenty ei ht.

S ANLEY S. GREEN.

means to feed liquid conductor from the container into aliquid-receiving end of the tube to interconnect the electrodes, andsaid tube being positioned upon s'uch interconnection to causecurrent-carrying liquid conductor Within itto occupy a lower level withrespect .to the container than the level occupied by the saine liquidconductor in the container before saidl feeding process, the other endof said tube being positioned to provide a. vent above the liquid levelvduring said feeding process.

23. An overload-protective electric circuit controller comprising acontainer, liquid conductor, an insulating ontrol-tube capable ofholding a portion of said liquid conductor, two electrodesinterconnectible by liquid conductor along a path extending lengthwisethrough said control tube, said control tube communicating at one endwith the conv taineigja vent tube having one opening communicating withthe interior of the container and another opening 'communicating withthe other end ofthe control-tube, said container being provided withmeans to feed liquid conductor downwardly into the control tube, and oneelecti'ode during such feeding process being spaced and insulated fromliquid conductor in the vent tube to prevent interconnection of saidelectrodes by liquid conductor along any path which does not include inseries with it the liquid conductor contained in the control tube.

24. An electric circuit controller, coniprising acontainer movable todifferent controlling positions including a normal circuitclosingposition, liquid conductor within the container, an insulating controltube having one end communicating with the container,A a conduit whichinterconnects the other end of said tube with the container, twoelectrodes interconnectible by liquid conductor along a path extendinglengthwise through said control tube, and connectingv means cooperatingwith the electrodes and through which the electrodes may be conv nectedin the controlled circuit, said connecting means being arranged to opensaid circuit when the movable container is 1n one controlling position.

